It is common practice to provide an auxiliary protective encasement for protecting electronic devices from impact damage. The typical protective case comprises an outer shell housing and an internally disposed elastomeric material placed upon the encasement bed designed to protect the electronic hardware from damaging impacting forces. Typically a shock absorbing protective insert is simply placed in the bed of the case. Normally, the front of the case is open for accessing the electronic device. Although the placement of certain shock absorbent inserts upon the encasement bed provides protection against transverse impact blows, there exists essentially no impact resistance against the more common impact damage caused by sidewise blows. This leaves a housed electronic hardware highly susceptible to damage by incoming sidewise impacting forces.
Not all elastomeric materials possess sufficient shock absorbent efficacy or physical integrity to protect delicate electronic hardware from multidirectional impact damage, or maintain their original structural static characteristics after impact, or have an ability to rebound gently, so as to provide superior damage resistance against a damaging impacting force. Almost all elastomeric materials lack the necessary compression and rebound characteristics to fully protect the most delicate electronic devices against impacting damage. Unfortunately, the more commonly used shock absorbing elastomeric materials provide only unilateral or compressive protection against impacting damage and often tend to become frayed, distorted or disintegrate when exposed to extended use or shocking blows. This problem becomes particularly acute as exemplified by the heretofore futile attempts to protect both the encasement bed and the internal side panels or inner cupped rim perimeters of a protective case with a highly effective thermoset viscoelastomeric protector, especially one susceptible to a confined deformation upon an application of external forces or pressures thereupon under confinement, such as applied by its covering with a plastic film. This problem is further compounded by the fact that a particular class of these viscoelastomeric materials also possesses a high degree of surface tack, leading to unsightly dust and other external contaminants, as well as having an undesirable surface tack feeling to the user. Prior attempts to cover such tacky surfaced, viscoelastomeric shock absorbing polymeric materials with a thin plastic film have been unsuccessful. As a protective barrier, such viscoelastomers fluid flow characteristics poise a particularly difficult challenge. Unlike conventional elastomers, which merely undergo compressive volume reduction upon impact and then decompress, certain of the most highly effective viscoelastomers merely become displaced, without any volumetric change occurring upon receiving a deforming impact. Thus, a slight surface pressure, such as applying a non-tacky film or coating upon the thermoset viscoelastomeric protector, will maintain the protector in its distorted state and prevent its restoration to its indigenous viscoelastomeric configuration (often referred to as “static” configuration). In addition, such trapped distortion also leads to a substantial loss of shock absorbing efficacy. The thermoset viscoelastomers, coupled with their tacky surface, thus tend to cohesively bond with an applied film or coating under a deforming pressure, such that the applied plastic film or coating retains the viscoelastomer in its deformed form and inhibits it from any reconfiguration to its native static form. Unfortunately, it has been virtually impossible to apply a plastic film to certain shock absorbing thermoset viscoelastomeric protectors. This covering problem is especially acute around the inner cornering cupped rims of such protective electronic cases, wherein the viscoelastomeric inlay becomes entrapped, deformed and restrained within the cupped inner rim from rebounding to its unique indigenous or static viscoelastomeric form. The applied covering film restrains and maintains the thermoset viscoelastomer polymeric inlay in its deformed state, thus severely eliminating the full benefit of its indigenous impact force arresting attributes of the thermoset viscoelastomer. Futile attempts to apply plastic films or coatings to the viscoelastomeric inlay have led to an unattractive finished product. As a result, many electronic case manufacturers have simply resorted to placing a tacky viscoelastomeric shock absorbing panel upon the encasement bed, while leaving the peripheral rim area unshielded from a protective film covering. This procedure is less difficult in that the viscoelastomeric inlay is not entrapped in its deformed state, as is the case of applying a film over a channeled inlay.
It would be highly advantageous if it were possible to apply a thin, non-tacky, protective plastic coating over a tacky, deformable, thermoset viscoelastomeric polymeric protector housed within a channeled inner rim of a protective encasement, especially without deleteriously altering the innate shock arresting properties of the inlaid thermoset viscoelastomeric protector.